1. Field of the Invention
The present invention relates, in general, to a personal ventilation apparatus and, in particular, to a personal ventilation system including a ventilation garment and air circulation apparatus for circulating air to parts of the body where ventilation is most needed. The invention relates especially to a personal ventilation system that may, in addition to circulating ambient air to selected parts of the body for evaporative cooling, be adapted to modify the ambient air for a specific operating environment to provide, for example, cooled, heated and/or filtered air to selected parts of the body.
2.Prior Art
A person working in a warm environment or performing tasks for which protective clothing is required may find the working conditions uncomfortable and may even experience a deterioration in performance or increased fatigue due to the build-up of body heat. Surgeons or staff working in operating rooms, for example, typically wear protective clothing which limits air circulation next to the body and inhibits evaporative cooling. Likewise, technicians working in clean room environments or with toxic waste cleanup crews or the like wear such protective gear. This may result in elevated body temperatures and increased stress.
One technique for keeping the body cool in such situations has been to employ a coolant-chilled garment. A coolant liquid such as chilled water is pumped through tubes which are attached to the garment to chill the garment. Such systems are typically closed systems in which the coolant is circulated through a cooling unit to maintain the garment and coolant at a chilled temperature. Although the entire system may be self contained, a person wearing the chilled garment must be tethered at all times to the cooling unit. The tether, of course, restricts the mobility of the wearer of the garment. Cooling by means of a liquid increases the weight the cooling garment and also the complexity and cost of the system. In addition, the cooling and tank units that are required for the liquid coolant may impede the movements of the wearer or others when the system is used in confined areas or when movement in the work area is necessary.
There have been systems employing air or refrigerated air for cooling individuals. However, these systems have been uncomfortable to wear, cumbersome to use, and frequently have the same disadvantages as the liquid cooling systems.
There is a need for a personal cooling system for use in garments required in environments such as operating rooms, clean rooms or similar environments that does not have the disadvantages of a liquid cooling system or the prior air cooling systems. In general, the personal body cooling system should be lightweight and comfortable so that additional stress is not placed on the wearer due to the cooling system itself. It is desirable that the personal cooling system be self-contained on the body of the wearer to allow the wearer to move freely without any tethers.
In order to interfere as little as possible with the normal activities of the wearer, the personal cooling system should not interfere with the mobility and manual dexterity of the wearer. The cooling system preferably should be reusable or, alternatively, inexpensive so that reuse is not necessary.
There is likewise a need for a personal system having the foregoing characteristics and advantages for use in other environments such as where heating, filtering or other modifications of an individual's environment are desired.